Beginning with the work of the economist Joan Robinson in the 1930’s, the word “monopsony" has been used in economics to refer to any market situation in which the buyer of a good possesses market power (i.e. some ability to choose the price at which they buy), regardless of whether or not there is actually only a single such buyer. Although monopsony power may be an important phenomenon in many different contexts, a growing body of research has focused on identifying and quantifying its extent in labor markets. Unfortunately, the existing empirical literature on this topic has thus far not meaningfully addressed one especially significant question, namely: to what extent do firms exploit all of the potential monopsony power available to them in setting the wages of their workers? The goal of our proposed study is to directly explore this question by using the CEEDD to simultaneously estimate both wage markdowns, or reduction of wages below what would be earned in a perfectly competitive market where firms have no wage-setting power, as well as the “full'' markdowns that would be predicted by standard models of an imperfectly competitive labor market, given the labor supply elasticity facing particular firms (a measure of how likely workers are to quit in response to wage cuts). Our hope is that these estimates will allow us to measure not only the average extent to which firms utilize their available wage-setting power, but also to explore heterogeneity in the same and to identify relevant correlates of being a “high-utilization" or “low-utilization" (of monopsony power) firm. We are particularly interested in studying whether firms with governance structures that allow for employee participation, including collective bargaining, are less aggressive monopsonists, as predicted by recent theoretical work on the topic.